the valleys, below the snow-line. They are often horizontal, generally, however, a little inclined. The ice of the glaciers is entirely different from that of the sea and river water. It is not formed in layers, but consists of little grains of congealed snow; and hence, though perfectly clear and often smooth on' the surface, it is not transparent. Its fracture is not radiated, like that of sea-ice, but granular. In the numerous fissures, however, the ice near the surface has a greenish, near the bottom, a blue cast. Along the edges of the glaciers, are the moraines, as they are called in Savoy (in Iceland, jökelsgiärde). They consist of an accumulation of earth, which is often several fathoms high, and, in summer, present the appearance of bottomless morasses, producing no vegetation. It is probable that these moraines are produced by the melting of the lower part of the glacier, which always takes place in summer, without which the annual accumulation of snow, in winter, would form an endless crust. The great ice-fields are also continually extending further down into the valleys, where, in summer, they are at last partially melted by the warmer temperature. In Lapland, where the sun has less power, glaciers slide down in the region of the Sulitelma, which render the air so cool, that the line of perpetual snow extends as low as 3000 feet above the level of the sea. The descent of the glaciers, which is assisted, in summer, by the avalanches, is greater or less, according to the inclination of the glacier. This is shown by the changes in the position of large masses of rock around the glaciers. They are evidently pushed along by the ice, and, near the Grindelberg, in Switzerland, it has been found, by examination, that stones nave been pushed forward 25 feet in one year. Stones of considerable bulk are also seen in the moraines of an entirely different formation from those of the valley, and must therefore have been pushed down from the higher regions in the course of time. As glaciers, in some positions, and in hot summers, decrease, they often also increase for a number of years, so as to render a valley uninhabitable. Their increase is caused partly by alternate thawing and freezing; their decrease, by the mountain rivers, which often flow under them, and thus form an arca of ice over the torrent. Streams are seen at the bottom of the deepest fissures, which, in the Helvetic Alps, are called dust or powder avalanches, because they consist of newly fallen snow, which

is carried by the wind into the depths. There are also, particularly in the Norwegian Alps, dirt avalanches, so called, which carry along stones and earth with them, and increase the moraines of the glaciers. In the Tyrol, Switzerland, Piedmont and Savoy, the glaciers are so numerous that they have been calculated to form altogether a superficial extent of 1484 square miles. There are some glaciers, in Savoy, more than 14 miles long, 24 miles wide, and from 60 to 600 feet thick. One of the most famous glaciers is the mere de glace (sea of ice) in the valley of Chamouni, about 5700 feet above the level of the sea. In France, near Beaume, and in the Carpathian mountains, near Dselitz, are subterraneous glaciers, which never melt, because the sun cannot act upon them. From this account, it is evident that there can be no glaciers in the Andes, because the temperature continues the same the whole year between the tropics. The noise which is produced by the opening of fissures in the glaciers is immense, and resembles thunder among the mountains. These fissures are often immediately covered with snow, and are therefore very dangerous to travellers. (See Avalanches.)

GLACIS, in fortification, is the sloping covering of the outer breastwork along the covered way, which descends to the level ground, and cover the ditch upon the outside. It must be so placed, that the guns of the fort will rake it at every point.

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GLADIATORS Were combatants, who fought at the public games, in Rome, for the entertainment of the spectators. They were at first prisoners, slaves or condemned criminals; but afterwards freemen fought in the arena, either for hire, or from choice. The regular gladiators were instructed in schools intended for this purpose. The overseer of this school purchased the gladiators, and maintained them. They were hired of him by those who wished to exhibit games to the ple. The games were commenced by a prælusio, in which they fought with weapons of wood, till, upon a signal, they assumed their arms, and began in earnest to fight in pairs. In case the vanquished was not killed in the combat, his fate was decided by the people. If they decreed his death, the thumb was held up in the air: the opposite motion was the signal to save him. In general, they suffered death with wonderful firmness, and the vanquished often exposed himself to the death-blow. If he wished to appeal to the people, he raised his hand. When

a gladiator was killed, attendants, appointed for the purpose, dragged the body, with iron hooks, into a room destined for this purpose. The victor received a branch of palm or a palm garland. The gladiators were often released from further service, and received, as the badge of freedom, a wooden sword (rudis).

Gladiatorial Statues. The most celcbrated gladiatorial statues are-1. the gladiator Borghese, which Winckelmann considered to be the statue of a warrior, or of a caster of the discus. Lessing thought it the statue of Chabrias; Nibby supposed it to be the statue of a Gaul, from the acroterium of the temple of Apollo at Delphi, which had been placed there in commemoration of the defeat of the Gauls before the city. It is a combatant, with extended arm, in the act of warding off a blow. It is a statue of the first rank, made of fine grained marble, and is now in the capitol, to which it was restored from Paris, 1815. 2. The dying gladiator, purchased from the Ludovisian collection for the Museum Capitolinum. It is a dying warrior, according to Zoega, a barbarian, who has received a wound in his breast, and is in the act of falling, with an expression of rage. The mustachios and the rope on the neck are perhaps the work of a modern artist, Michael Angelo.

GLAIR EGGS is the same as the white of eggs, used as a varnish for preserving paintings. For this purpose, it is beat to an unctuous consistence, and commonly mixed with a little brandy or spirits of wine, to make it work more freely, and with a little lump sugar, to give it body, and prevent its cracking, and then spread over the picture with a fine, elastic brush. GLAMOUR, OF GLAMER; an old term of popular superstition, in Scotland, denoting a kind of magical mist believed to be raised by sorcerers.

GLANVIL, OF GLANVILLE, Ranulph de; an English baron of the 12th century, celebrated as a lawyer and a warrior. He was of Norman descent; and, in the reign of Henry II, held the office of justiciary of the kingdom. It was at that period that he signalized his valor in repelling the invasion of England by William, king of Scotland, who was taken prisoner as he was besieging the castle of Alnwick. Richard I, after his accession to the crown, is said to have imprisoned Glanvil, and obliged him to pay for his freedom the sum of £15,000 towards the expenses of a crusade to the Holy Land. The aged magistrate accompanied his

master on the expedition to which he had so largely contributed, and perished, together with a vast multitude of other English warriors, at the siege of Acre, in 1190. To judge Glanvil is attributed a curious treatise on the laws and customs of England, which was first published in 1554. A translation, by John Beames, of Lincoln's Inn, appeared in 1812, with a life of the author.

GLARUS, one of the smallest cantons of the Swiss confederacy, the seventh in rank, surrounded by the cantons of St. Gall, the Grisons, Uri and Schweitz, contains 445 square miles, with 24,000 inhabitants, of whom 4000 are Catholics, the others Calvinists. On all sides, except towards the north, Glarus is walled in by glaciers and mountains covered with snow. The river Linth flows through it. In 1352, it joined the Swiss confederacy. The inhabitants are distinguished for their industry. The constitution is a pure democracy. The capital,

Glarus, situated on the Linth, has 4000 inhabitants. It lies at the foot of the Glärnisch, a mountain 9500 feet high. It contains a Catholic church, several schools, considerable manufactories, &c. The green cheese, called Schabzieher, is made here. Four miles below Glarus, on the Linth, is Näfels, where the inhabitants twice defeated (1352 and 1388) superior numbers of Austrians.

GLASGOW; a city of Scotland, in the county of Lanark, which has been long distinguished for its extensive commerce and manufactures. It is one of the most ancient towns in Scotland, its origin being generally attributed to St. Mungo, or St. Kentigern, who is said to have founded a bishopric here in the year 560, which was afterwards erected into an archiepiscopal see in 1484. The principal part of the city occupies a plain on the north side of the river Clyde. Its length and breadth are scertained by two main streets which, cross each other at right angles, and run, the one east and west, about one mile and a half, and the other, north and south, three fourths of a mile long. Of the publie buildings in Glasgow, the cathedral, or high church, at the north end of the High street, is a splendid edifice, and perhaps the most entire specimen of Gothic architecture that is to be found in Scotland. It is 284 feet long, 65 broad, and 90 feet high within the walls, with two large towers, on one of which a spire was built about the year 1420, making the whole 220 feet in height. Of the other churches, the most remarkable are S

David's, St. Enoch's and St. Andrew's. A Roman Catholic chapel was erected in 1816. There are altogether within the city 10 parish churches, besides the barony; 7 chapels connected with the establishment, besides 25 meeting houses for different classes of dissenters. The Glassites, Bereans, Universalists, &c., have all places of worship. The college buildings, and the houses for the accommodation of the professors, are very extensive, having a front of 305 feet to the High street, and 282 feet from east to west. This celebrated seminary of education was founded in 1450, by William Turnbull, bishop of Glasgow. About 1400 students attend the university. There is a valuable and extensive library. The celebrated doctor William Hunter, of London, bequeathed to the university his whole museum, one of the most valuable collections in Europe, of natural history, paintings, medals, anatomical preparations, books, &c. At present, the establishment in the university consists of a lord chancellor, lord rector, dean of faculty, the principal and professors of divinity, church history, Oriental languages, natural philosophy, mathematics, moral philosophy, logic, Greek, humanity, civil law, materia medica, anatomy, practical astronomy, and the regius professors of natural history, surgery, midwifery, chemistry and botany. There is also another institution, where lectures are given on natural and experimental philosophy, on mathematics, on chemistry, botany and natural history. There are numerous charitable institutions, various hospitals for the sick and infirm, a lunatic asylum, a Magdalen asylum, besides charity schools. The suburbs, both to the north and south, on the opposite shore of the Clyde, are connected with the body of the city by three handsome bridges. The Clyde is navigable for vessels draw-. ing seven or eight feet water, as far as the lowest bridge; and a quay, extending a quarter of a mile down the river, affords every accommodation for trade. The manufacture of linens, lawns, cambrics, and other articles of similar fabric, was introduced into Glasgow about the year 1725, when it was superseded, in 1787, by the introduction of muslins. In 1785, the dyeing of cottons in turkey red color was begun; and a manufactory of Bandana handkerchiefs has been since established. Previous to the union, the trade of Glasgow was chiefly confined to Holland and France. After this, however, the English colonies being opened to the Scotch, Glasgow engaged extensively in the trade of Virginia

and Maryland, importing chiefly tobacco. The West India trade afforded another outlet to the increasing capital of Glasgow, and this branch of commerce has been since greatly extended. Glasgow is celebrated for its great establishments for the cotton manufacture. There are 54 works for weaving by power, which contain 3700 looms, producing 1,924,000 pieces, containing 48,000,000 yards, annually; and it appears, from a late investigation, that there are about 32,000 hand looms. There are 12 calender houses, which have 32 calenders moved by steam. These calender daily 296,000 yards of cloth, besides dressing 530,000, and glazing 30,000 yards. There are 38 calico printing works, 16 brass founderies, and 310 steam engines, connected with the city. About the year 1172, Glasgow was erected into a burgh by William (surnamed the Lion), king of Scotland. In 1611, James VI granted the city a very ample charter, by which it was erected into a royal burgh. The communication of Glasgow with the country along the shores of the Clyde, has been greatly aided by the use of steam-boats, of which there are now 46 plying on the Clyde. It communicates also with the surrounding country by various canals. The suburbs are extensive, and contain several populous and industrious villages, which carry on extensive manufactures. There are also several printfields and extensive bleachfields in the vicinity of the place. Population, in 1780, 42,832; in 1791, 66,578; in 1801, 83,769; in 1811, 110,460; in 1821, 147,043. Lon. 4° 15′ 51′′ W.; lat. 55° 52′ 10′′ N.

GLASS doubtless owes its origin to chance. Pliny informs us that Sidon was the first city distinguished for its glass-works, and that the manufacture of glass was not introduced into Rome until the reign of Tiberius. He further states, that, in the reign of Nero, the art of making vases and cups of a white, transparent glass, was invented. De Pauw is of opinion that the Egyptians carried the art to the highest perfection; and that the glassworks at Diospolis, capital of the Thebaid, were the first regular manufactory of this material. The Egyptians, according to the same author, performed the most difficult operations in glass-cutting, and manufactured cups of glass of an astonishing purity, of which kind were those called alassontes, supposed to be ornamented with figures in changeable colors. Winckelmann says that the ancients, in general, made much greater use of glass

than the moderns. Besides the ordinary utensils, of which a great quantity have been found in Herculaneum, we find many funeral urns constructed of it. Some of the fragments of cups examined by Winckelmann, appeared to have been cut; some of the raised ornaments having the appearance of being soldered to the surface of the vessels, and bearing marks of the lapidary's wheel on their facettes. The ancients also used glass to ornament their rooms; for this purpose, they employed it of various colors, and composed a sort of mosaic of it. Some blocks of glass, used for paving rooms, have been found, of the thickness of a common sized brick. Winckelmann cites some specimens of mosaic of remarkable beauty and delicacy. One of them represented a bird on a dark and colored ground. The colors of the bird were very brilliant and various, and the whole effect very soft. The artist had made use of opaque or transparent glass, according to the exigencies of the case. What was not the least remarkable was, that the reverse offered precisely the same figure, without the slightest difference in the details. A little glass ring, which was in the possession of Mr. Hamilton, revealed the method in which this was performed. The exterior of the ring was blue, and the interior represented a species of rose, of different colors, extending the whole circuit of the ring. As melted glass may be drawn out into an amazingly fine wire, this operation may be performed on pieces of glass, compounded of different colors and melted, the colors preserving the respective layers when wire-drawn. Caylus thinks this was the manner in which these works of art were made. The most valuable remains of the ancients, in glass, are the impressions and casts of sculptured gems, both in sunk and raised work, and the larger works in relief, of which one whole vase has come down to us. The glass casts of intaglios often imiate the veins of different colors in the original. These pastes have preserved the impressions of many beautiful gems, which are lost. Of the larger works in relief we have only some fragments: they served as ornaments to the walls of palaces. The most considerable work of this kind is the cameo described by Buonarotti, and preserved in the Vatican: it is an oblong tablet of glass, about 8 inches by 6, representing Bacchus and Ariadne, with two satyrs. But the most beautiful specimens of this art are the vases adorned with figures in relief: they were sometimes transparent, sometimes of different

colors on a dark ground, and so delicately executed, that they were hardly to be distinguished from the vases of sardonyx. The Portland vase is the only one of this sort preserved entire. It was formerly called the Barberini vase, as it belonged to the Barberini palace at Rome. It is about a foot high, and was at first described as a sardonyx. (See Portland Vase.) The ancients were also acquainted with the art of painting on glass (see a subsequent division of this article).

Glass is made by melting silicious earth or sand, alkaline substances, and metallic oxide, at a white heat. The name is an old German word, and is connected with gleissen (to shine), and with the English word glisten, and even with glacies (ice) and glanz (splendor). The manufacture of glass is now brought to a high degree of perfection, especially in England. The English glass-houses are commonly large conical buildings, from 60 to 100 feet high, and from 50 to 80 feet in diameter. The furnace is in the middle, over a large vault, which is connected with it by means of an opening. This opening is covered with an iron grate, upon which the fire is made, and it is kept up by the draught of air from the vault. The most important part, however, of the apparatus of the glass-house, is the crucible. These instruments are made from a particular kind of clay, which is found at Stourbridge. This is first pounded fine, then sifted, moistened, and worked into a thick dough. Sometimes old crucibles are used, which are broken into powder, and then mixed with a red clay. Some pots, for bottle and flint glass, are made 40 inches deep and wide. They are from two to four inches in thickness. They remain several days at a white heat, before they are placed in the furnace. The basis of glass is silica. Much of the silicious sand used in the U. States comes from the banks of the Delaware. When flints or quartz are used, they are first reduced to powder by being heated red hot, and then plunged into cold water. This causes them to whiten and fall to pieces, after which they are ground and sifted. The second ingredient is an alkaline substance, potash or soda. The alkali used is more or less pure, according to the fineness of the glass to be made. Lime is often em ployed in small quantities; also borax. Of the metallic oxides added in different cases, the deutoxide of lead is the most common. It renders flint glass more fusible, heavy and tough, and more easy to be ground and cut, increases its brilliancy and

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refractive power. A small quantity of black oxide of manganese renders the glass more transparent; too much gives a purple tinge, which, however, may be destroyed by a little charcoal or wood. Arsenious acid (white arsenic), in small quantities, promotes the clearness of glass; too much of it gives the glass a milky whiteness. Its use in drinking-vessels is not free from danger, if the glass contains so much alkali that any part is soluble in acids. The following are the processes employed in making glass:

Fritting. The various materials are carefully washed, and, after the extraction of all the impurities, are conveyed to the furnace in pots made of tobacco-pipe clay. The produce of this process is called the frit, which is again melted in large pots or crucibles, till the whole mass becomes beautifully clear, and the dross rises to the top. Blowing is the next process, which, in round glass, as phials, drinkingglasses, &c., is thus performed: The workmen dip the end of long iron pipes, red hot, into the liquid glass, then roll it on a polished iron plate to give it an external even surface; they next blow down the iron pipe, till it enlarges the metal like a bladder, and, if necessary, roll it again on the iron plate, and proceed to form it into a globular form, or any other one required. The glass is then transferred from the blowing pipe, by dipping the end of another iron rod into the liquid glass, which adheres to the heated rod, and with which the workman sticks it to the bottom of the vessel; then, with a pair of pincers, wetted with water, he touches the neck, which immediately cracks, and, on being slightly struck, separates at the end of the blowing-pipe, and becomes attached to the iron rod. The vessel is next carried up to the mouth of the furnace, to be heated and softened, that the operator may finish it. If the vessel require a handle, the operator forms it separately, and unites it while melting hot, forming it with pincers to the requisite shape and pattern.-Annealing is the removing of the glass, after it has been blown or cast, into a furnace, whose heat is not sufficiently intense to melt it; and, gradually withdrawing the article from the hottest to a cooler part of the annealing chamber, till it is cold enough to be taken out for use. If cooled too suddenly, it is extremely brittle.-Coloring. The different colored glasses owe their tints to the different metallic oxides mixed with the materials while in a state of fusion. (See Gems. In this manner are

made those elegant pastes, which so faithfully imitate, and not unfrequently excel, in brilliancy, their originals, the gems of antiquity. The glass, however, for this purpose, is prepared in a peculiar manner, and requires great nicety. It combines purity and durability. Opaque glass is made by the addition of the oxide of tin, and produces that beautiful imitation of enamel which is so much admired. Dials for watches and clocks are thus made. The principal sorts of glass are the following: Crown Glass, the best window glass, is made of white sand, purified barilla, saltpetre, borax and arsenic, melted together; and, if the glass assume a yellowish hue, the defect is removed by adding a sufficient quantity of manganese. (See Crown Glass.)-Newcastle Glass, generally used in England, is of an ash color, frequently speckled, streaked and blemished. It is made from white sand, unpurified barilla, common salt, arsenic and manganese. The Bottle or Green Glass, usually made of common sand, lime, and some clay, fused with an impure alkali, is very hard, and resists the corrosive action of all liquids much better than flint glass: the green color is owing to the iron: it is well adapted for chemical vessels.-Flint Glass, the most fusible of any, is used for bottles, utensils intended to be cut and polished, and for various ornamental purposes. The best kind is composed of white silicious sand, pearlash, red oxide of lead, nitrate of potash, and the black oxide of manganese. It fuses at a lower temperature than crown glass, has a beautiful transparency, a great refractive pow er, and a comparative softness, which enables it to be cut and polished with ease. On this account it is much used for glass vessels of every description, and especially those which are intended to be ornamented by cutting. It is also einployed for lenses and other optical glasses. Flint glass is worked by blowing, mould. ing, pressing and grinding. Articles of complex form, such as lamps and wineglasses, are formed in pieces, which are afterwards joined by simple contact, while the glass is hot. It appears that the red lead, used in the manufacture of flint glass, gives up a part of its oxygen, and passes to the state of a protoxide.-Plate Glass, so called from its being cast in plates or large sheets, is the most valuable, and is used for mirrors and the windows of carriages. It is composed of white sand, cleansed with purified pearlashes and borax. But should the metal appear yellow, it is restored to its pellucid transpa